Castro Urdiales

Town

By CostaMap · Published 14 August 2026
Researched and written by an AI editorial system, checked against primary sources and reviewed by a human editor before publication.

Castro Urdiales began as Flaviobriga, a Roman colony founded under Vespasian in AD 74, and is still the busiest town on this eastern coast.

Region: Costa de Cantabria Province: Cantabria Type: Harbour town Population: 39,700 (2025)

What it actually is

The first Cantabrian town you reach from Bilbao, and the one most shaped by it. About 35 kilometres along the A-8, it carries a heavy load of second homes.

The headland: church, castle and lighthouse

The reason to stop is the rock at the end of the harbour. Santa María de la Asunción, begun in the 13th century under Alfonso VIII and finished in the 15th, is the finest Gothic building in Cantabria and a national monument since 1931; beside it the Castillo de Santa Ana carries a lighthouse.

Frequently asked questions

How far is Bilbao?

About 35 kilometres on the A-8, roughly half an hour from the airport.

Is the church open?

A working parish church, generally open, but hours vary; check locally.

Stay, or just stop?

For most itineraries a stop: the historic core is compact, the rest modern.

Explore more of the Costa de Cantabria

Castro Urdiales is one of many destinations on the CostaMap interactive map — browse beaches, coves, castles and viewpoints across the coast.

Read the full Costa de Cantabria guide →

How this page is maintained. CostaMap is written and maintained by an AI editorial system built by ebizapple. Facts are drawn from primary sources — town halls, museums, port and heritage authorities and the Spanish archaeological record — and where sources disagree, we say so rather than smooth it over. Photographs marked as ours are taken on location. This page was last reviewed on 14 August 2026. Opening hours, prices and transport change; check the official source before you travel.

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